U.S. Pat. No. 3,888,750 discloses a process for decomposing water which involves the following electrolytic reactions: EQU SO.sub.2 +2H.sub.2 O.fwdarw.H.sub.2 SO.sub.4 +2H.sup.+ +2e.sup.-( 1) EQU 2 H.sup.+ +2 e.sup.- .fwdarw.H.sub.2 ( 2)
These reactions take place in an electrolytic cell, the first reaction occurring at the anode and the second reaction at the cathode.
One of the difficulties in making this process efficient has been finding an anode which would be stable in the concentrated sulfuric acid anolyte and which would require as little electrical energy as possible to oxidize the SO.sub.2 to sulfuric acid. Until now the best anode that has been found is a porous carbon plate which has been impregnated with a platinum catalyst. While a carbon plate anode works satisfactorily in the cell, it has poor long-term stability and requires more electrical energy to oxidize the sulfur dioxide than is desirable. Also, the carbon plate anode is not flexible and therefore can be easily broken when incorporated in a cell stack which is generally used for constructing a hydrogen production plant.